1. Cross-Reference To Related Applications.
This application is related to the co-pending application of Charles L. Adams, Ser. No. 07/386,455, filed July 27, 1989, U.S. Pat. No. 4,968,069, entitled "Bolt-On Flange", and assigned to the assignee of the present invention.
2. Field of the Invention.
The present invention relates to water storage vessels of the type used for potable water supplies and, particularly, to such vessels designed for use as water heaters and to methods of making the same.
3. Description of the Prior Art.
A variety of water heater and hot water storage vessel designs are known which typically feature a metallic vessel body, often formed of steel, having a water inlet, a water outlet and at least one additional opening. The additional opening can receive, for example, a heat generating means. In order to provide potable water fit for human consumption, it is necessary to line the vessel body with a material which resists the corrosive attack of water, including the corrosive attack of water containing such common corrosion agents as carbon dioxide, oxygen, chloride ions, sulfate ions, and the like. In the past, the lining was typically applied by spraying on a plastic type material or molding in a corrosion resistant material, as by using a slush type molding process. U.S. Pat. No. 3,207,358, issued Sept. 21, 1965, to Fliss, shows a method of corrosion protecting a water heater in which an inner layer formed of an epoxy resin is covered with an outer layer of a thermoplastic chlorinated polyether resin. The manufacturing process includes multiple spray and curing steps. The commonly called "glass lined" water heaters available commercially have interior surfaces which are coated with a porcelain enamel type material. The assignee of the present invention has, for a number of years, provided water heaters having interiors covered with an electroless nickel which forms a non-ferrous corrosion resistant protective shield within the vessel body.
While the prior designs accomplish their intended purpose of providing corrosion protection, they are time consuming and expensive from a manufacturing standpoint. Also, because the lining was sprayed or molded and therefore integrally bonded to the vessel interior, it was not possible to easily repair or replace a damaged or worn liner.
The present invention has as its object to provide a hot water storage vessel with an improved liner arrangement which resists the corrosive attack of water containing common corrosion agents to thereby ensure a supply of potable water fit for human consumption.
Another object of the invention is to provide a hot water storage vessel having a metallic body and a flexible, non-molded liner which covers substantially the entire interior of the vessel body, the liner being easily installed with a minimum of effort and expense.
Another object of the invention is to provide such a vessel having a replaceable liner which facilitates repair operations so that it is not necessary to discard the vessel body in the case of a damaged or defective liner.
Additional objects, features and advantages will be apparent in the written description which follows.